CN209067209U - A kind of shield tunnel end joint reinforcement structure - Google Patents

Abstract

The utility model discloses a kind of shield tunnel end joint reinforcement structures, the generally rectangular box structure of joint reinforcement structure, rectangular box structure is to be enclosed to set by four sides ruggedized construction, wherein the ruggedized construction close to foundation pit is frozen soil wall, the ruggedized construction in excess-three face is cement soil continuous wall.Its method are as follows: Step 1: the construction of cement soil continuous wall: using TRD engineering method using the method construction equal thickness cement soil continuous wall of three circulations；Step 2: the construction of vertical frozen soil wall: carrying out the drilling construction of freezing hole first, the installation of Freezing Station is carried out simultaneously, after determining that freezing to meet portal cuts condition, start to abolish hole cell wall, forced thaw before shield host export & import, vertical frozen pipe, thaw settlement grouting are extracted after to shield host export & import；The utility model has the advantages that construction is practical, quality control on construction is convenient, consolidation effect is prominent, expires hall than traditional cement mixing method and reinforce saving construction cost, there is biggish application value.

Description

A kind of shield tunnel end joint reinforcement structure

Technical field

The utility model relates to a kind of joint reinforcement structure, in particular to a kind of shield tunnel end joint reinforcement structure.

Background technique

The reinforcing of shield tunnel end is the key link in shield construction, has very big engineering construction risk.In shield When structure export & import, the diaphram wall that first carry out portal region is abolished, and cuts off all reinforcing bars.Portal abolishes the time of requirement Very tight, difficulty of construction is big.Portal is very high to reinforcing body intensity and sealing requirements after abolishing, when consolidation effect is bad, in hole Easily there is shield in door when abolishing and portal gap gushes mud and gushes sand and ground settlement phenomenon, and then jeopardizes underground utilities nearby and build Build the safety of object.To prevent such phenomenon from occurring, it is necessary to reasonable shield tunnel end stratum consolidation processing scheme is selected, with full Sufficient intensity and impervious requirement.

The common reinforcing mode in shield tunnel end have deep mixing method, high-pressure rotary spraying method, SMW engineering method, engineering with artificial freezing method, Slip casting method, plain concrete bored cast-in-situ pile and precipitation method etc..What soil stabilization can be combined using a kind of engineering method or a variety of engineering methods Reinforcing means.Reinforcing mode should be according to engineering geological condition, level of ground water, structure buried depth, shield mainframe type and diameter, operation ring The conditions such as border are selected, while considering the factors such as safety, property easy for construction, economy, duration.

When coastal soft clay area, especially shield tunnel end stratum are rich aquifer sand layer, added using conventional chemistry Gu means are extremely difficult to engine request, serious leak sand leakage phenomenon can have usually been found when inspecting hole after chemical consolidation.At this point, being Shield tunnel end soil body intensity and abundant sealing are improved, guarantees shield export & import safety, how to be selected in rich aquifer sand layer end Selecting stratum consolidation mode is the technical issues that need to address.

Summary of the invention

Purpose of the utility model is to solve when shield tunnel end stratum is rich aquifer sand layer how selectively The problem of layer reinforcing mode and a kind of shield tunnel end joint reinforcement structure for providing.

The generally rectangular box structure of shield tunnel end joint reinforcement structure provided by the utility model, rectangular box Structure is to be enclosed to set by four sides ruggedized construction, wherein the ruggedized construction close to foundation pit is frozen soil wall, the reinforcing knot in excess-three face Structure is cement soil continuous wall.

The insertion depth of vertical frozen pipe is 1-2m in the impermeable stratum of lower section in frozen soil wall, and vertical frozen pipe lays length and is Each 3m in shield tunnel two sides, vertical frozen pipe diameter are 127mm or 108mm or 169mm；Vertical frozen pipe arranges 1-3 row, flower arrangement Arrangement, the spacing of vertical frozen pipe are 800mm, and the vertical frozen pipe close to active well building enclosure is apart from cell wall side 300- 400mm, vertical frozen pipe are implemented overall length and are freezed, and the material of vertical frozen pipe is seamless low carbon steel pipe or PVC plastic pipe or PPR modeling Expects pipe or ABS plastic pipe or PE plastic tube, the section of vertical frozen pipe are round or " I-shaped " or " X-shaped " or " T shape " or " Y Shape ".

The wall thickness of cement soil continuous wall is 600-850mm, and insertion depth is 1-2m in the impermeable stratum of lower section, and soil cement is continuous Wall paper sets length as shield host length+(2-3) B sealing thickness, and wherein B is section of jurisdiction width.

The construction method of shield tunnel end joint reinforcement structure provided by the utility model, method are as described below:

Step 1: the construction of cement soil continuous wall: using TRD engineering method using the method construction equal thickness soil cement of three circulations Diaphragm wall, Specific construction technique are as follows:

(1), surveying setting-out: before construction, the coordinate basis point first provided according to design drawing accurately calculates soil cement company Continuous center line of wall angular coordinate carries out setting-out using measuring instrument, and carries out coordinate data review, while carrying out fender pile, and lead to Know that relevant unit carries out unwrapping wire review；

(2), it excavates groove: after cement soil continuous wall center line setting-out, laying steel plate being carried out to construction site and is reinforced Processing, it is ensured that construction site meets requirement of the mechanical equipment to foundation bearing capacity, it is ensured that the stability of stake machine, with excavator along water Excavate working channel, groove width 1.2m, trench depth 1.0m in soil diaphragm wall centerline parallel direction；

(3), it hangs provided box: with the pre-buried cave of excavator cutting depth 3m, length 2m, width 1m, using crane and inciting somebody to action Provided box is hung in pre-buried cave；

(4), stake machine is in place: assuming unified command of that stake machine is in place by squad leader on duty, sees upper and lower, left and right various aspects clearly before mobile Situation, discovery have barrier to remove in time, check positioning scenarios and timely correction after mobile, stake is confidential steady, straight and even；

(5), cutting box and host connect: being hung cutting box into pre-buried cave paragraph by paragraph with specified tracklaying crane, utilized Supporting table is fixed；Connection cutting box is set at TRD host mobility to pre-buried acupuncture point, and TRD host returns again to predetermined construction location and cut It cuts case and voluntarily squeezes into excavation process；

(6), inclinometer is installed: after cutting box is voluntarily driven into projected depth, inclinometer being installed, by being mounted on cutting box Internal multisection type inclinometer, is able to carry out the vertical precision management of wall, it is ensured that the precision within 1/250；

(7), TRD engineering method is at wall: after the installation is completed, TRD host is connect inclinometer with cutting box, carries out three process equal thickness Cement soil continuous wall construction, specific process are as follows:

Process 1-is excavated in advance: being injected by mudjack and is excavated liquid, cutting box is pushed ahead, and is excavated and is loosened native soil layer, cuts It is cut into slot a trip；

Process 2-withdraws excavation: according to operation work efficiency, after the completion of the grooving of a trip, cutting box is withdrawn again to cutting Starting point；

Process 3-stir at wall: cutting box exchanges slurries after withdrawing to cutting starting point, is injected and is solidified by mudjack Liquid, cutting box are pushed ahead and are mixed with liquid mixing mud is excavated, and uniform thickness cement soil continuous wall is formed；

(8), mud is tested: being carried out mud test to slurries and mixing mud in water-stop curtain work progress, including is excavated Liquor ratio weight excavates liquid mixing mud fluidity, solidify liquid specific gravity and solidify liquid mixing mud specific gravity；

(9), displacement soil processing: by the unified stacking of the discarded slurry generated in TRD engineering method work progress, centralized processing；

(10), it extracts cutting box: after stirring at wall, acting the solidification pulled out region and inject same proportion drafting cutting box Liquid, side rise and draw out slip casting, it is ensured that occupy cavity to cutting box and carry out dense packing effect and effectively reinforce, terminate straightway wall and apply Work；

Step 2: the construction of vertical frozen soil wall:

Frozen construction is before shield host driving, and the method manually freezed will be aqueous in active well end regions Freezing stratum as rapid completely cuts off underground water, guarantees the disengaging of shield host at a fluid-tight curtain of closing for resisting ground pressure, hydraulic pressure The safety in hole；

The drilling construction of freezing hole is carried out first, while carrying out the installation of Freezing Station, after freezing hole construction, into Row freezing hole series pipe and heat insulation work, are then actively freezed, and are observed and being calculated by thermometer hole, and determination is freezed to meet hole After door cuts condition, start to abolish hole cell wall, forced thaw before shield host export & import, while by vertical frozen pipe extract to Shield host top maintain freeze, to shield host export & import after extract vertical frozen pipe, thaw settlement grouting, concrete technology is such as Under:

(1), freeze design:

(1), Frozen wall thickness designs: incorporation engineering feature, soil layer condition and construction site situation are to freezing curtain thickness It is designed, the vertical frozen soil wall thickness close to active well building enclosure is greater than 1.6m；

1), freezing curtain physical parameter:

Frozen soil mean temperature takes -10 DEG C, and frozen soil strength index carries out laboratory test and determines；

2), reinforcing body size:

Longitudinal length: shield host length+(2-3) B sealing thickness, wherein B is section of jurisdiction width；

Transverse width: each 3m in shield tunnel two sides；

Depth: implement overall length and freeze.

(2), the arrangement of freezing hole: freezing hole arranges 1-3 row, and flower arrangement arrangement, pitch of holes 800mm, arranging spacing is 800mm, the vertical frozen hole close to active well building enclosure is apart from cell wall side 300-400mm；

(3), thermometer hole is arranged: being adjusted according to the deflection situation of drilling to the position of thermometer hole, is measured freezing curtain The temperature development situation of range different parts, to take corresponding control measure, it is ensured that the safety of construction；

(2), refrigerant system design:

(1), parameter is chosen:

1), vertical frozen pipe selects the seamless low carbon steel pipe of 127 × 4.5mm of φ；

2) when, using salt water coolant media, freezing period outlet brine temp be -28~-30 DEG C, circuit brine temp be - 25~-28 DEG C；

3), salt water specific gravity 1.26；

4), brine flow 5m in freezing pipe³/h；

5), freezing pipe heat-sinking capability: 260Kcal/m².h；

6), loss of refrigeration capacity coefficient: 1.2；

(2), chilling requirement calculates:

Freeze chilling requirement calculating: Q=1.2 π dHK

In formula: H-freezes total length；

D-freezes pipe diameter；

K-freezing pipe coefficient of heat transfer；

(3), Freezing Station setting, Unit Selection and quantity:

Freezing Station selects II type screw rod refrigerator two of W-YSLGF600, every unit 28 × 104Kcal/h of refrigerating capacity, electricity Machine power 220kw；

(4), brine system:

1), salt water conduit tube, collection brine distributing ring type selecting: φ 159 × 5mm welded tube processing and fabricating；

2) it, 80% crystal calcium chloride dosage: supplies according to the actual situation；

3) three IS150-125-315 type centrifugal water pumps, flow 200m, brine pump type selecting: are selected³/ h, motor 30kw；

(5), clean water system:

1), water pipe type selecting: φ 133 × 4.5mm welded tube processing and fabricating；

2) 8m, is selected³Filtered water tank three；

3), fresh water magnitude of recruitment: 30m³/h；

4) three IS150-125-315 type centrifugal water pumps, flow 200m, are selected³/ h, motor 30kw；

5) KST-80 type cooling tower four, is selected；

(6), freezing pipe designs: vertical frozen pipe selects the seamless low carbon steel pipe of 127 × 4.5mm of φ, and horizontal frozen pipe is selected 108 × 8mm of φ is seamless low carbon steel pipe；Liquid supply pipe selects 45 × 4mm of φ seamless steel pipe；

(7), frost wall forms prediction: according to freezing curtain development speed 25mm/ days, vertical frozen pipe maximum pitch of holes was taken 800mm, then handing over the circle time is t1=800/2/25=16 days, and the closure of freezing wall time takes 20 days, and entire actively freeze-off time takes 30 days；

(3), drilling construction:

(1), drilling device type selecting:

XP-30B engineering driller two are selected, matches one, Te Lasi air compressor machine GR200-20 type, using percussion drilling work Skill；

It is being drilled in hole using setting of casing deviational survey, using Inclination Measurement by Light or JDT-5 type gyrolevel deviational survey is being used, to protect Card drilling vertical precision；

(2), drilling technique requirement:

When drilling, by the needs of depth and strata condition, increase and decrease drill collar in time, accomplish and uniformly, at the uniform velocity creep into, forbids suddenly fast Suddenly slow, pressure is suddenly big or suddenly small；

Revolving speed, pressure and flushing dose are rationally grasped, when adding ruler or more bit change, is swept under drilling tool at away from bottom hole 0.3-0.5m Hole, brigadier's drilling tool is not parked in a depth and rinses for a long time, and when power failure, drilling tool is mentioned to safety depth, is had a power failure more than 2 hours, general Drilling tool all proposes, to the frequent detailed inspection of all drilling tools, bent drill pipe is forbidden to use with excessive drilling rod is worn, whole hole Shi Fuhe Drilling tool overall length, and punching empties rock powder, then down tube；

Freezing pipe first carries out ground combo, measures overall length, makes a record, and when down tube removes foreign object in pipe, keeps cleaning, examination After pressure seal mouth, the gap around freezing pipe is tamped in time with soil, prevents mud string hole；

Deflection: the freezing hole deviation proportion that is averaged is not greater than 5 ‰, and freezing hole end pitch of holes is not more than design value, otherwise gives Perforations adding, the depth of freezing meet design requirement, and lower length of tube freezes hole depth not less than design；

Deviational survey: it uses light theodolite to carry out whole hole and pore-forming deviational survey during freezing hole construction and draws freezing hole in time Deflection plane figure；

Drill site basis: in order to guarantee drilling quality, scene is laid with simple mud groove；

(4), frozen construction:

(1), frozen construction capital equipment: equipment is as shown in the table:

In the case where being lost according to power load total during freezing and line voltage distribution, entire refrigeration station selects YC3 × 120 + 2 × 25 low pressure Plastic-sheathed Cables three freeze unit and corresponding corollary equipment for two respectively；

(2), Freezing Station is installed: Freezing Station is arranged in side, and two units are installed in parallel, can be mutually spare, and Freezing Station accounts for 200 square metres of ground；

(3), the installation of unit is freezed:

1), in place with fixation:

According to Freezing Station layout drawing, will freeze unit it is in place after, be reliably fixed with bolt and basis, water when fixed Leveling ruler is levelling to unit progress, is leveled unit by constantly adjusting parallels；

It is arranged according to the pipeline at scene, two epicranial plate of condenser is adjusted flexibly, the arrangement of optimization pipeline is had reached, by unit Starting cabinet is securely arranged in beside unit, and certain space is left between unit, to be brought to Operation and Maintenance usually It is convenient；

2), piping connection: flanged joint is used between saline line and clear water pipeline and unit, and arranges installation valve；

3), unit sealing detection: freezing unit be sealed, first carry out refrigeration system leak detection, ensure system without After rushing down leakage, then fill fluorine oiling；

4), unit refuels: checking that the amount of refrigerator oil in unit will refuel if very few to unit, freezing unit is selected 46^#Refrigerator oil；

(4), clear, brine pump installation: water pump and motor are checked, it is ensured that do not damage in transportation and handling procedure；Inspection Tool and hoisting machinery, and the basis of inspection machine are looked into, the basic plane for installing pump will carry out level leveling, examine again after placing The levelness of whole unit is consulted, respective bracket is arranged in the suction line and discharge pipeline of pump, and pipe weight cannot be direct It is born by pump, pump shaft and motor direction of rotation are consistent, and the suction inlet of pump is higher than clear, brine tank bottom 20cm, in fresh water pump Suction inlet installs one of strainer, and one of strainer is arranged among brine tank, checks that the junction of pump, pipeline and pump and pipeline has Non-loosening phenomenon rotates pump shaft with hand, checks whether pump shaft rotation is flexible, bearing lubrication machine oil, observation are added into bearing body Oil level will will be replaced or be supplemented in time in the centerline of oil ga(u)ge, lubricating oil；

(5), the installation of cooling tower: Fire Hazard Area in cooling tower installation process is forbidden to be welded in tower body and its neighbouring use Or gas cutting work with torches, in field mustn't personnel's smoking, cooling tower foundation keeps horizontal, and pillar is vertical with basal plane, each basal plane height difference No more than ± 1mm, center is ± 2mm away from tolerance, and when tower body assembly, bolt is symmetrically fastened, and does not allow to distort installation by force, spelling After dress must not leak, cooling tower column foot and basic fixation, cooling tower components do not permit thereon during transport, storage Perhaps ballast must not be exposed to the sun, and pay attention to open fire, cooling tower inlet tube and outlet tube and supplement water pipe support of pipelines is separately provided, avoid by Pipeline weight transmitting tower body；Fan blade is kept properly, and prevents from deforming, and motor and driving member will oil, and is stored indoors, cooling Tower after the installation is completed, remains in cleaning pipeline, filler surface and dirt and tower in water-collecting tray, and carry out system flush；

(6), it freezes unit regulation: before refrigeration system debugging, having to the cleaning for carrying out internal system and dry work, Specific works are as follows:

1), the filling of refrigerant:

After in-site installation, visual examination does not have accidental injury, if it find that refrigerant has leaked or insufficient, finds out and lets out Leak source simultaneously excludes leakage phenomenon, and refrigerant is then added, and is filled with from dedicated filling liquid valve；

2) it, debugs:

Simulated action inspection side is done to main electric-control system before formal booting, i.e. unit host no power, control system is powered, Then by unit inner setting, the electric-control system of unit is detected, component whether normal operation, if electric-control system goes out Existing problem, solves in time, finally leads to upper host power supply again, is debugged；

In debugging process, the following is paid attention to:

Check that whether valve is in normal open state, especially discharge line valve everywhere in refrigeration system, is sure not It closes；

The flow of the cooling water valve of opening condenser and the Cold water tap of evaporator, cold water and cooling water will meet unit Technical requirements；

Notice whether the supply voltage of observation unit is normal before starting；

3) it, runs:

According to the requirement of refrigerator operating instruction, start unit；

After unit starting, is required according to unit specification, check whether the parameters of unit are normal；

The all data of unit is recorded, major parameter will record clear；

In unit running process, notice whether the increasing of compressor, off-load mechanism work normally；

The safety guard installed in proper use of refrigeration system, as high-low pressure protective device, cold water and cooling water are disconnected Water flow switch and safety valve, if any damage replacement in time；

4), exception monitoring

Such as there is abnormal conditions, hard stop inspection in screw-type water chiller；

The mark that screw type refrigerating compressor operates normally are as follows:

The gauge pressure of Compressor Discharge Pressure is 0.8-1.5MPa；

Compressor exhaust temperature is 45-90 DEG C；

The oil temperature of compressor is 40-55 DEG C；

The gauge pressure of compressor oil pressure table is 0.2-0.3MPa；

Sound is uniform, steady in compressor operational process, sound without exception；

The condensation temperature of unit is 3-5 DEG C higher than cooling water temperature；Condensation temperature control is at 40 DEG C, condenser inflow temperature Control is at 32 DEG C or less；

The evaporating temperature of unit is 3-4 DEG C lower than the leaving water temperature of chilled water, and condensed water leaving water temperature is 5-7 DEG C；

(7), clear, brine pump debugging:

Whether there is or not loose phenomenons for the junction of inspection pump, pipeline and pump and pipeline, rotate pump with hand, try that pump shaft rotation is It is no flexible；

Bearing lubrication machine oil is added into bearing body, observation oil level should be replaced in time in the centerline of oil ga(u)ge, lubricating oil Or supplement；

Crawl motor tries whether motor steering is correct；

Motor is started, after pumping normal operation, outlet pressure is opened, after showing pressure depending on it, is gradually opened gate valve, together When check motor load situation；

It is excessive whether the observation pump housing and pipeline vibrate, and parking checking reason is wanted when excessive and is handled；

In the range that the flow and lift for controlling pump indicate on label, to guarantee that pump is operated in best efficiency point；

In the process of running, for bearing temperature no more than 35 DEG C of environment temperature, maximum temperature must not exceed 80 DEG C to pump, such as send out Now pump has abnormal sound parking checking reason immediately；

(8), other: to freeze machine oil and select N46 refrigerator oil；Refrigerant selects freon R-22；Refrigerant agent selects calcium chloride Solution；

(5), cell wall is abolished:

Abolish the condition that cell wall has: frozen soil wall thickness >=1.6m；Mean temperature≤- 10 DEG C of frozen soil；Brine temp -28 DEG C~-30 DEG C；Salt water go loop temperature it is poor≤2 DEG C；Inspecting hole temperature≤- 2 DEG C；

It is observed by inspecting hole, judges the freezing efficiency of frozen soil wall, after freezing 30 days, cell wall first has point before abolishing on portal Cloth drills through several inspecting holes, to judge that the cementing situation of frozen soil and cell wall, inspecting hole depth enter 10-15cm in frozen soil wall, then, It is measured using temperature measurer, it is desirable that each inspecting hole observed temperature has to be lower than -2 DEG C, surveys when by inspecting hole observed temperature and level Warm hole observed temperature judge frozen soil wall and cell wall completely it is reliable it is cementing can whole broken walls；

(6), vertical frozen pipe is pulled out:

(1), it forced thaw: using the scheme manually locally thawed, is recycled in frigo using hot salt brine, makes vertically to freeze The frozen soil tied around pipe melts；

(2), salt water heats: with a 3m³Brine tank store salt water, carry out heating salt with the heating wire of six groups of 20kw Water, temperature are controlled at 75 ± 10 DEG C；

(3), brine recycling: utilize brine pump circulating brine, Model of pump IS150-125-315, each freezing hole Brine recycling flow control is in 5-7m³/h；

(4), it thaws and measures: using the thermometer hole in freezing curtain, the variation of daily Timing measurement curtain temperature, until freezing Until knot curtain rises to positive temperature, then stop defrosting operation；

(5), rising for vertical frozen pipe is pulled out: after vertical frozen pipe thaws, with compressed air will manage in salt water discharge, using hanging Vehicle carries out examination and pulls out, when pulling up 0.5m or so, it is ensured that after without exception, quickly extracts vertical frozen pipe, tube drawing pays attention to vertical frozen pipe Want being aligned with hook, vertical frozen pipe cannot sprain strength, when tube drawing will normal micro- rotation vertical frozen pipe, vertical frozen pipe cannot be hard It pulls out, when such as pulling out motionless, hot salt brine defrosting is continued cycling through, until it can pull up vertical frozen pipe；

(7), frost heave and thaw collapse control:

Frost heave is the soil expansion because of caused by water freezing when freezing soil, and following controlling measurement is taken to freeze in work progress Swollen and thaw collapse:

(1), after the extraction of vertical frozen pipe, it is closely knit that the filling of hole yellow ground will be freezed in time；

(2), in the thawing stage of frozen soil body, slip casting densification is carried out to consolidation by freezing area using the injected hole of tunnel duct piece and is added Gu the freeze thawing soil body takes small pressure, the mode of more notes time to carry out slip casting, grouting pressure 0.2-0.5MPa, slurries select single liquid Cement slurry；

(3), for pre- anti-freeze expansion and thaw collapse, the big freezing unit of selection standard refrigerating capacity is designed, in a short time salt Coolant-temperature gage drops to design value, to accelerate frozen soil development, improves frozen soil strength, reduces frost heave and thaw collapse amount；

(4), grasp and adjust brine temp and brine flow, take it is intermittent freeze, frozen soil development amount is controlled, to reduce Frost heave and thaw collapse.

The construction parameter of TRD engineering method is as follows in step 1:

(1), it excavates liquid mixing and uses sodium bentonite, every cube is stirred soil body incorporation 100kg/m³Bentonite, water ash It is 5-20 than W/B, work progress adds 50-200kg bentonite mixing slurries by 1000kg water；

(2), the control of liquid mixing mud fluidity is excavated in 190mm-240mm；

(3), it excavates liquid voluntarily to squeeze into process for cutting box, excavate process in advance, withdraws and excavate process view mixing mud Fluidity injection excavate liquid；

(4), solidify liquid mixing uses P42.5 grades of ordinary portland cements, and every cube is stirred soil body incorporation and is no less than 25% cement, the ratio of mud 1.5, the every 937kg water of work progress add 625kg cement mixing slurries；

(5), the control of solidify liquid mixing mud fluidity is in 180mm-220mm；

(6), solidify liquid is used in into wall agitating procedure.

TRD engineering method is called equal thickness Soil-cement continuous wall constructing method including, by Japanese kobe steel 1993 exploitation one It kind is continuously constructed equal thickness Soil-cement continuous wall construction technique using saw chain formula cutting box.The engineering method is in general sandy soils The depth capacity of middle construction has reached 56.7m, wall thickness 550mm-850mm, is also applied for all kinds of stratum such as boulder and cobble, block stone.

The utility model has the beneficial effects that

Shield tunnel end joint reinforcement structure provided by the utility model and construction method construction depth are big, depth capacity Up to 60m；It is wide to adapt to stratum, there is good excavation performance to hardpan (pan soil, sand boulder and cobble, soft rock etc.)；At wall Quality is good, on wall depth direction, it is ensured that uniform soil cement quality, intensity improve, and discreteness is small, and the performance that intercepts water is good； High security, center of gravity is low, and stability is good, the place suitable for limited height；Continuously at wall, seam is less, wall uniform thickness, H Fashioned iron can best spacing setting；Noise, vibration are smaller.

Practical, quality control on construction is convenient, consolidation effect especially water-stagnating effect is good with constructing for the utility model And outstanding advantages of safe and reliable, expire hall than traditional cement mixing method and reinforce saving construction cost, there are biggish popularization and application Value.

Detailed description of the invention

Fig. 1 is joint reinforcement structural front view described in the utility model.

Fig. 2 is joint reinforcement structure top view described in the utility model.

Fig. 3 is TRD engineering method construction technology process schematic diagram described in the utility model.

Fig. 4 is vertical frozen construction technology process schematic diagram described in the utility model.

Fig. 5 is drilling construction flow diagram described in the utility model.

It is as shown in the figure:

1, frozen soil wall 2, cement soil continuous wall 3, vertical frozen pipe 4, building enclosure

5, shield host.

Specific embodiment

It please refers to shown in Fig. 1 to Fig. 5:

The generally rectangular box structure of shield tunnel end joint reinforcement structure provided by the utility model, rectangular box Structure is to be enclosed to set by four sides ruggedized construction, wherein the ruggedized construction close to foundation pit is frozen soil wall 1, the reinforcing knot in excess-three face Structure is cement soil continuous wall 2.

The insertion depth of vertical frozen pipe 3 is 1-2m in the impermeable stratum of lower section in frozen soil wall 1, and vertical frozen pipe 3 lays length Degree is each 3m in shield tunnel two sides, and 3 diameter of vertical frozen pipe is 127mm or 108mm or 169mm；Vertical frozen pipe 3 arranges 1-3 Row, flower arrangement arrangement, the spacing of vertical frozen pipe 3 are 800mm, and the vertical frozen pipe 3 close to active well building enclosure 4 is apart from cell wall Side 300-400mm, vertical frozen pipe 3 are implemented overall length and are freezed, and the material of vertical frozen pipe 3 is seamless low carbon steel pipe or PVC plastic Pipe or PPR plastic tube or ABS plastic pipe or PE plastic tube, the section of vertical frozen pipe 3 be round or " I-shaped " or " X-shaped " or " T shape " or " Y shape ".

The wall thickness of cement soil continuous wall 2 is 600-850mm, and insertion depth is 1-2m in the impermeable stratum of lower section, and soil cement connects It is 5 length of shield host+(2-3) B sealing thickness that continuous wall 2, which lays length, and wherein B is section of jurisdiction width.

The construction method of shield tunnel end joint reinforcement structure provided by the utility model, method are as described below:

Step 1: the construction of cement soil continuous wall 2: using TRD engineering method using the method construction equal thickness cement of three circulations Native diaphragm wall 2, Specific construction technique are as follows:

(1), surveying setting-out: before construction, the coordinate basis point first provided according to design drawing accurately calculates soil cement company Continuous 2 center line angular coordinate of wall carries out setting-out using measuring instrument, and carries out coordinate data review, while carrying out fender pile, and lead to Know that relevant unit carries out unwrapping wire review；

(2), it excavates groove: after 2 center line setting-out of cement soil continuous wall, laying steel plate being carried out to construction site and is reinforced Processing, it is ensured that construction site meets requirement of the mechanical equipment to foundation bearing capacity, it is ensured that the stability of stake machine, with excavator along water Excavate working channel, groove width 1.2m, trench depth 1.0m in 2 centerline parallel direction of soil diaphragm wall；

(3), it hangs provided box: with the pre-buried cave of excavator cutting depth 3m, length 2m, width 1m, using crane and inciting somebody to action Provided box is hung in pre-buried cave；

(4), stake machine is in place: assuming unified command of that stake machine is in place by squad leader on duty, sees upper and lower, left and right various aspects clearly before mobile Situation, discovery have barrier to remove in time, check positioning scenarios and timely correction after mobile, stake is confidential steady, straight and even；

(5), cutting box and host connect: being hung cutting box into pre-buried cave paragraph by paragraph with specified tracklaying crane, utilized Supporting table is fixed；Connection cutting box is set at TRD host mobility to pre-buried acupuncture point, and TRD host returns again to predetermined construction location and cut It cuts case and voluntarily squeezes into excavation process；

(6), inclinometer is installed: after cutting box is voluntarily driven into projected depth, inclinometer being installed, by being mounted on cutting box Internal multisection type inclinometer, is able to carry out the vertical precision management of wall, it is ensured that the precision within 1/250；

(7), TRD engineering method is at wall: after the installation is completed, TRD host is connect inclinometer with cutting box, carries out three process equal thickness Cement soil continuous wall construction, specific process are as follows:

Process 1-is excavated in advance: being injected by mudjack and is excavated liquid, cutting box is pushed ahead, and is excavated and is loosened native soil layer, cuts It is cut into slot a trip；

Process 2-withdraws excavation: according to operation work efficiency, after the completion of the grooving of a trip, cutting box is withdrawn again to cutting Starting point；

Process 3-stir at wall: cutting box exchanges slurries after withdrawing to cutting starting point, is injected and is solidified by mudjack Liquid, cutting box are pushed ahead and are mixed with liquid mixing mud is excavated, and uniform thickness cement soil continuous wall 2 is formed；

(8), mud is tested: being carried out mud test to slurries and mixing mud in water-stop curtain work progress, including is excavated Liquor ratio weight excavates liquid mixing mud fluidity, solidify liquid specific gravity and solidify liquid mixing mud specific gravity；

(9), displacement soil processing: by the unified stacking of the discarded slurry generated in TRD engineering method work progress, centralized processing；

(10), it extracts cutting box: after stirring at wall, acting the solidification pulled out region and inject same proportion drafting cutting box Liquid, side rise and draw out slip casting, it is ensured that occupy cavity to cutting box and carry out dense packing effect and effectively reinforce, terminate straightway wall and apply Work；

Step 2: the construction of vertical frozen soil wall:

Frozen construction is before the driving of shield host 5, and the method manually freezed will be aqueous in active well end regions Freezing stratum as rapid completely cuts off underground water, guarantees that shield host 5 passes in and out at a fluid-tight curtain of closing for resisting ground pressure, hydraulic pressure The safety in hole；

The drilling construction of freezing hole is carried out first, while carrying out the installation of Freezing Station, after freezing hole construction, into Row freezing hole series pipe and heat insulation work, are then actively freezed, and are observed and being calculated by thermometer hole, and determination is freezed to meet hole After door cuts condition, start to abolish hole cell wall, forced thaw before 5 export & import of shield host, while vertical frozen pipe 3 being extracted To 5 top of shield host maintain freeze, to 5 export & import of shield host after extract vertical frozen pipe, thaw settlement grouting, specific work Skill is as follows:

(1), freeze design:

(1), Frozen wall thickness designs: incorporation engineering feature, soil layer condition and construction site situation are to freezing curtain thickness It is designed, 1 thickness of vertical frozen soil wall close to active well building enclosure 4 is greater than 1.6m；

1), freezing curtain physical parameter:

Frozen soil mean temperature takes -10 DEG C, and frozen soil strength index carries out laboratory test and determines；

2), reinforcing body size:

Longitudinal length: 5 length of shield host+(2-3) B sealing thickness, wherein B is section of jurisdiction width；

Transverse width: each 3m in shield tunnel two sides；

Depth: implement overall length and freeze.

(2), the arrangement of freezing hole: freezing hole arranges 1-3 row, and flower arrangement arrangement, pitch of holes 800mm, arranging spacing is 800mm, the vertical frozen hole close to active well building enclosure 4 is apart from cell wall side 300-400mm；

(3), thermometer hole is arranged: being adjusted according to the deflection situation of drilling to the position of thermometer hole, is measured freezing curtain The temperature development situation of range different parts, to take corresponding control measure, it is ensured that the safety of construction；

(2), refrigerant system design:

(1), parameter is chosen:

1), vertical frozen pipe 3 selects the seamless low carbon steel pipe of 127 × 4.5mm of φ；

2) when, using salt water coolant media, freezing period outlet brine temp be -28~-30 DEG C, circuit brine temp be - 25~-28 DEG C；

3), salt water specific gravity 1.26；

4), brine flow 5m in freezing pipe³/h；

5), freezing pipe heat-sinking capability: 260Kcal/m².h；

6), loss of refrigeration capacity coefficient: 1.2；

(2), chilling requirement calculates:

Freeze chilling requirement calculating: Q=1.2 π dHK

In formula: H-freezes total length；

D-freezes pipe diameter；

K-freezing pipe coefficient of heat transfer；

(3), Freezing Station setting, Unit Selection and quantity:

Freezing Station selects II type screw rod refrigerator two of W-YSLGF600, every unit 28 × 104Kcal/h of refrigerating capacity, electricity Machine power 220kw；

(4), brine system:

1), salt water conduit tube, collection brine distributing ring type selecting: φ 159 × 5mm welded tube processing and fabricating；

2) it, 80% crystal calcium chloride dosage: supplies according to the actual situation；

3) three IS150-125-315 type centrifugal water pumps, flow 200m, brine pump type selecting: are selected³/ h, motor 30kw；

(5), clean water system:

1), water pipe type selecting: φ 133 × 4.5mm welded tube processing and fabricating；

2) 8m, is selected³Filtered water tank three；

3), fresh water magnitude of recruitment: 30m³/h；

4) three IS150-125-315 type centrifugal water pumps, flow 200m, are selected³/ h, motor 30kw；

5) KST-80 type cooling tower four, is selected；

(6), freezing pipe designs: vertical frozen pipe 3 selects the seamless low carbon steel pipe of 127 × 4.5mm of φ, and horizontal frozen pipe is selected 108 × 8mm of φ is seamless low carbon steel pipe；Liquid supply pipe selects 45 × 4mm of φ seamless steel pipe；

(7), frost wall forms prediction: according to freezing curtain development speed 25mm/ days, 3 maximum pitch of holes of vertical frozen pipe 800mm is taken, then handing over the circle time is t1=800/2/25=16 days, and the closure of freezing wall time takes 20 days, entire positive freeze-off time It takes 30 days；

(3), drilling construction:

(1), drilling device type selecting:

XP-30B engineering driller two are selected, matches one, Te Lasi air compressor machine GR200-20 type, using percussion drilling work Skill；

It is being drilled in hole using setting of casing deviational survey, using Inclination Measurement by Light or JDT-5 type gyrolevel deviational survey is being used, to protect Card drilling vertical precision；

(2), drilling technique requirement:

When drilling, by the needs of depth and strata condition, increase and decrease drill collar in time, accomplish and uniformly, at the uniform velocity creep into, forbids suddenly fast Suddenly slow, pressure is suddenly big or suddenly small；

Revolving speed, pressure and flushing dose are rationally grasped, when adding ruler or more bit change, is swept under drilling tool at away from bottom hole 0.3-0.5m Hole, brigadier's drilling tool is not parked in a depth and rinses for a long time, and when power failure, drilling tool is mentioned to safety depth, is had a power failure more than 2 hours, general Drilling tool all proposes, to the frequent detailed inspection of all drilling tools, bent drill pipe is forbidden to use with excessive drilling rod is worn, whole hole Shi Fuhe Drilling tool overall length, and punching empties rock powder, then down tube；Freezing pipe first carries out ground combo, measures overall length, makes a record, down tube When remove foreign object in pipe, keep cleaning in time to tamp the gap around freezing pipe with soil after pressure testing sealing, prevent mud string Hole；

Deflection: the freezing hole deviation proportion that is averaged is not greater than 5 ‰, and freezing hole end pitch of holes is not more than design value, otherwise gives Perforations adding, the depth of freezing meet design requirement, and lower length of tube freezes hole depth not less than design；

Deviational survey: it uses light theodolite to carry out whole hole and pore-forming deviational survey during freezing hole construction and draws freezing hole in time Deflection plane figure；

Drill site basis: in order to guarantee drilling quality, scene is laid with simple mud groove；

(4), frozen construction:

(1), frozen construction capital equipment: equipment is as shown in the table:

In the case where being lost according to power load total during freezing and line voltage distribution, entire refrigeration station selects YC3 × 120 + 2 × 25 low pressure Plastic-sheathed Cables three freeze unit and corresponding corollary equipment for two respectively；

(2), Freezing Station is installed: Freezing Station is arranged in side, and two units are installed in parallel, can be mutually spare, and Freezing Station accounts for 200 square metres of ground；

(3), the installation of unit is freezed:

1), in place with fixation:

According to Freezing Station layout drawing, will freeze unit it is in place after, be reliably fixed with bolt and basis, water when fixed Leveling ruler is levelling to unit progress, is leveled unit by constantly adjusting parallels；

It is arranged according to the pipeline at scene, two epicranial plate of condenser is adjusted flexibly, the arrangement of optimization pipeline is had reached, by unit Starting cabinet is securely arranged in beside unit, and certain space is left between unit, to be brought to Operation and Maintenance usually It is convenient；

2), piping connection: flanged joint is used between saline line and clear water pipeline and unit, and arranges installation valve；

3), unit sealing detection: freezing unit be sealed, first carry out refrigeration system leak detection, ensure system without After rushing down leakage, then fill fluorine oiling；

4), unit refuels: checking that the amount of refrigerator oil in unit will refuel if very few to unit, freezing unit is selected 46^#Refrigerator oil；

(4), clear, brine pump installation: water pump and motor are checked, it is ensured that do not damage in transportation and handling procedure；Inspection Tool and hoisting machinery, and the basis of inspection machine are looked into, the basic plane for installing pump will carry out level leveling, examine again after placing The levelness of whole unit is consulted, respective bracket is arranged in the suction line and discharge pipeline of pump, and pipe weight cannot be direct It is born by pump, pump shaft and motor direction of rotation are consistent, and the suction inlet of pump is higher than clear, brine tank bottom 20cm, in fresh water pump Suction inlet installs one of strainer, and one of strainer is arranged among brine tank, checks that the junction of pump, pipeline and pump and pipeline has Non-loosening phenomenon rotates pump shaft with hand, checks whether pump shaft rotation is flexible, bearing lubrication machine oil, observation are added into bearing body Oil level will will be replaced or be supplemented in time in the centerline of oil ga(u)ge, lubricating oil；

(5), the installation of cooling tower: Fire Hazard Area in cooling tower installation process is forbidden to be welded in tower body and its neighbouring use Or gas cutting work with torches, in field mustn't personnel's smoking, cooling tower foundation keeps horizontal, and pillar is vertical with basal plane, each basal plane height difference No more than ± 1mm, center is ± 2mm away from tolerance, and when tower body assembly, bolt is symmetrically fastened, and does not allow to distort installation by force, spelling After dress must not leak, cooling tower column foot and basic fixation, cooling tower components do not permit thereon during transport, storage Perhaps ballast must not be exposed to the sun, and pay attention to open fire, cooling tower inlet tube and outlet tube and supplement water pipe support of pipelines is separately provided, avoid by Pipeline weight transmitting tower body；Fan blade is kept properly, and prevents from deforming, and motor and driving member will oil, and is stored indoors, cooling Tower after the installation is completed, remains in cleaning pipeline, filler surface and dirt and tower in water-collecting tray, and carry out system flush；

(6), it freezes unit regulation: before refrigeration system debugging, having to the cleaning for carrying out internal system and dry work, Specific works are as follows:

1), the filling of refrigerant:

After in-site installation, visual examination does not have accidental injury, if it find that refrigerant has leaked or insufficient, finds out and lets out Leak source simultaneously excludes leakage phenomenon, and refrigerant is then added, and is filled with from dedicated filling liquid valve；

2) it, debugs:

Simulated action inspection side is done to main electric-control system before formal booting, i.e. unit host no power, control system is powered, Then by unit inner setting, the electric-control system of unit is detected, component whether normal operation, if electric-control system goes out Existing problem, solves in time, finally leads to upper host power supply again, is debugged；

In debugging process, the following is paid attention to:

Check that whether valve is in normal open state, especially discharge line valve everywhere in refrigeration system, is sure not It closes；

The flow of the cooling water valve of opening condenser and the Cold water tap of evaporator, cold water and cooling water will meet unit Technical requirements；

Notice whether the supply voltage of observation unit is normal before starting；

3) it, runs:

According to the requirement of refrigerator operating instruction, start unit；

After unit starting, is required according to unit specification, check whether the parameters of unit are normal；

The all data of unit is recorded, major parameter will record clear；

In unit running process, notice whether the increasing of compressor, off-load mechanism work normally；

The safety guard installed in proper use of refrigeration system, as high-low pressure protective device, cold water and cooling water are disconnected Water flow switch and safety valve, if any damage replacement in time；

4), exception monitoring

Such as there is abnormal conditions, hard stop inspection in screw-type water chiller；

The mark that screw type refrigerating compressor operates normally are as follows:

The gauge pressure of Compressor Discharge Pressure is 0.8-1.5MPa；

Compressor exhaust temperature is 45-90 DEG C；

The oil temperature of compressor is 40-55 DEG C；

The gauge pressure of compressor oil pressure table is 0.2-0.3MPa；

Sound is uniform, steady in compressor operational process, sound without exception；

The condensation temperature of unit is 3-5 DEG C higher than cooling water temperature；Condensation temperature control is at 40 DEG C, condenser inflow temperature Control is at 32 DEG C or less；

The evaporating temperature of unit is 3-4 DEG C lower than the leaving water temperature of chilled water, and condensed water leaving water temperature is 5-7 DEG C；

(7), clear, brine pump debugging:

Whether there is or not loose phenomenons for the junction of inspection pump, pipeline and pump and pipeline, rotate pump with hand, try that pump shaft rotation is It is no flexible；

Bearing lubrication machine oil is added into bearing body, observation oil level should be replaced in time in the centerline of oil ga(u)ge, lubricating oil Or supplement；

Crawl motor tries whether motor steering is correct；

Motor is started, after pumping normal operation, outlet pressure is opened, after showing pressure depending on it, is gradually opened gate valve, together When check motor load situation；

It is excessive whether the observation pump housing and pipeline vibrate, and parking checking reason is wanted when excessive and is handled；

In the range that the flow and lift for controlling pump indicate on label, to guarantee that pump is operated in best efficiency point；

In the process of running, for bearing temperature no more than 35 DEG C of environment temperature, maximum temperature must not exceed 80 DEG C to pump, such as send out Now pump has abnormal sound parking checking reason immediately；

(8), other: to freeze machine oil and select N46 refrigerator oil；Refrigerant selects freon R-22；Refrigerant agent selects calcium chloride Solution；

(5), cell wall is abolished:

Abolish the condition that cell wall has: 1 thickness of frozen soil wall >=1.6m；Mean temperature≤- 10 DEG C of frozen soil；Brine temp- 28 DEG C~-30 DEG C；Salt water go loop temperature it is poor≤2 DEG C；Inspecting hole temperature≤- 2 DEG C；

It is observed by inspecting hole, judges the freezing efficiency of frozen soil wall 1, after freezing 30 days, cell wall first has on portal before abolishing Distribution drills through several inspecting holes, to judge that the cementing situation of frozen soil and cell wall, inspecting hole depth enter 10-15cm in frozen soil wall 1, so Afterwards, it is measured using temperature measurer, it is desirable that each inspecting hole observed temperature has to be lower than -2 DEG C, when passing through inspecting hole observed temperature and horizontal Thermometer hole observed temperature judge frozen soil wall 1 and cell wall completely it is reliable it is cementing can whole broken walls；

(6), vertical frozen pipe 3 is pulled out:

(1), it forced thaw: using the scheme manually locally thawed, is recycled in frigo using hot salt brine, makes vertically to freeze The frozen soil tied around pipe 3 melts；

(2), salt water heats: with a 3m³Brine tank store salt water, carry out heating salt with the heating wire of six groups of 20kw Water, temperature are controlled at 75 ± 10 DEG C；

(3), brine recycling: utilize brine pump circulating brine, Model of pump IS150-125-315, each freezing hole Brine recycling flow control is in 5-7m³/h；

(4), it thaws and measures: using the thermometer hole in freezing curtain, the variation of daily Timing measurement curtain temperature, until freezing Until knot curtain rises to positive temperature, then stop defrosting operation；

(5), rising for vertical frozen pipe 3 is pulled out: after vertical frozen pipe 3 thaws, will be managed interior salt water discharge with compressed air, and be used Crane carries out examination and pulls out, when pulling up 0.5m or so, it is ensured that after without exception, quickly extracts vertical frozen pipe 3, tube drawing pays attention to vertical frozen Pipe 3 and hook want being aligned, and vertical frozen pipe 3 cannot sprain strength, when tube drawing will normal micro- rotation vertical frozen pipe 3, vertical frozen pipe 3 It cannot pull out firmly, when such as pulling out motionless, hot salt brine defrosting is continued cycling through, until it can pull up vertical frozen pipe 3；

(7), frost heave and thaw collapse control:

Frost heave is the soil expansion because of caused by water freezing when freezing soil, and following controlling measurement is taken to freeze in work progress Swollen and thaw collapse:

(1), after the extraction of vertical frozen pipe 3, it is closely knit that the filling of hole yellow ground will be freezed in time；

(2), in the thawing stage of frozen soil body, slip casting densification is carried out to consolidation by freezing area using the injected hole of tunnel duct piece and is added Gu the freeze thawing soil body takes small pressure, the mode of more notes time to carry out slip casting, grouting pressure 0.2-0.5MPa, slurries select single liquid Cement slurry；

(3), for pre- anti-freeze expansion and thaw collapse, the big freezing unit of selection standard refrigerating capacity is designed, in a short time salt Coolant-temperature gage drops to design value, to accelerate frozen soil development, improves frozen soil strength, reduces frost heave and thaw collapse amount；

(4), grasp and adjust brine temp and brine flow, take it is intermittent freeze, frozen soil development amount is controlled, to reduce Frost heave and thaw collapse.

The construction parameter of TRD engineering method is as follows in step 1:

(1), it excavates liquid mixing and uses sodium bentonite, every cube is stirred soil body incorporation 100kg/m³Bentonite, water ash It is 5-20 than W/B, work progress adds 50-200kg bentonite mixing slurries by 1000kg water；

(2), the control of liquid mixing mud fluidity is excavated in 190mm-240mm；

(3), it excavates liquid voluntarily to squeeze into process for cutting box, excavate process in advance, withdraws and excavate process view mixing mud Fluidity injection excavate liquid；

(4), solidify liquid mixing uses P42.5 grades of ordinary portland cements, and every cube is stirred soil body incorporation and is no less than 25% cement, the ratio of mud 1.5, the every 937kg water of work progress add 625kg cement mixing slurries；

(5), the control of solidify liquid mixing mud fluidity is in 180mm-220mm；

(6), solidify liquid is used in into wall agitating procedure.

TRD engineering method is called equal thickness Soil-cement continuous wall constructing method including, by Japanese kobe steel 1993 exploitation one It kind is continuously constructed equal thickness Soil-cement continuous wall construction technique using saw chain formula cutting box.The engineering method is in general sandy soils The depth capacity of middle construction has reached 56.7m, wall thickness 550mm-850mm, is also applied for all kinds of stratum such as boulder and cobble, block stone.

Claims (3)

1. a kind of shield tunnel end joint reinforcement structure, it is characterised in that: the generally rectangular box structure of ruggedized construction, square Shape box structure be enclosed to set by four sides ruggedized construction, wherein close to foundation pit ruggedized construction be frozen soil wall, excess-three face Ruggedized construction is cement soil continuous wall.

2. a kind of shield tunnel end joint reinforcement structure according to claim 1, it is characterised in that: the frozen soil wall The insertion depth of middle vertical frozen pipe is 1-2m in the impermeable stratum of lower section, and it is that shield tunnel two sides are each that vertical frozen pipe, which lays length, 3m, vertical frozen pipe diameter are 127mm or 108mm or 169mm；Vertical frozen pipe arranges 1-3 row, flower arrangement arrangement, vertical frozen The spacing of pipe is 800mm, and the vertical frozen pipe close to active well building enclosure is apart from cell wall side 300-400mm, vertical frozen pipe Implement overall length to freeze, the material of vertical frozen pipe is seamless low carbon steel pipe or PVC plastic pipe or PPR plastic tube or ABS plastic pipe Or PE plastic tube, the section of vertical frozen pipe are round or " I-shaped " or " X-shaped " or " T shape " or " Y shape ".

3. a kind of shield tunnel end joint reinforcement structure according to claim 1, it is characterised in that: the soil cement The wall thickness of diaphragm wall is 600-850mm, and insertion depth is 1-2m in the impermeable stratum of lower section, and it is shield that cement soil continuous wall, which lays length, Structure host length+(2-3) B sealing thickness, wherein B is section of jurisdiction width.